Vacuum cooling unit



March 29, 1938. M. FORNCROOK VACUUM COOLING UNIT Filed June 15, 1954 2 Sheets-Sheet l INVENTOR March 29,1938. FORNCROM 2,112,563

vAcuUi/I COOLING UNIT Filed June 15, 1934 2 Sheets- Sheet 2 INYVENTOR I v fiu #464;

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Patented Mar. 29, 1938 2,112,563

UNITED STATES PATENT OFFICE VACUUM COOLING UNIT Lawrence M. Forncrook, Pittsburgh, Pa., assignor to Elliott Company, Pittsburgh, Pa., a corporation of Pennsylvania Application June 13, 1934, Serial No. 730,459

7 Claims. (01. 62-152) Figure 1 is a side elevation showing one form of mouth of the diffuser portion 4 in the sense of apparatus constructed in accordance with my indownstream from such mouth when considering vention; the flow of fluid through the diffuser. In like Figure 2 is a diagrammatic vertical section on manner, the inlet 2! and the outlet i2 of the con- M a smaller scale illustrating the operation; and denser chamber are located behind the mouth of Figure 3 is a view similar to Figure 2 showing the diffuser portion 5 in the sense of upstream a modified form similar to that of Figures 1 and from such portion when considering the flow of 2, except that a tubular or surface condenser is fluid therethrough. It will also appear that theused therein. inlets and outlets of both the evaporator and con- My invention relates to vacuum-cooling apdenser chambers are located upstream from the 10 paratus of the steam jet type and is designed mouth of the diffuser portion 5. The fiow dito simplify, cheapen and improve such apparatus. rected by the spillways in both the evaporator and In Figures 1 and 2 of the form shown in the condenser chambers is substantially longitudinal drawings, a single tank or cooling unit indicated of the diffuser 4-5.

generally by the letter A is divided into two When in operation, steam of any desirable presl6 chambers indicated generally by the letters -B and sure is admitted and expanded through nozzle 3,

C. The upper head 2 is provided with a central thus changing pressure energy to Velocity ensteam-expanding nozzle 3 below and in line with ergy. A high velocity steam jet leaving this which is a central diffuser having the upper nozzle 3 entrains gas or vapors in chamber B,

downwardly contracting portion 4 within the and the mixture is driven into the upper portion 20 upper chamber and. the lower downwardly ex- 4 of the diffuser. This reduces the pressure in panding portion 5 within the lower chamber. chamber B and sets up a partial vacuum therein. The chambers are separated by a partition which The quantity of steam admitted through the noz preferably contains insulation, being shown as ale 3, together with the design of this nozzle and consisting of two plates 6 and I separated by an of the diffuser, will result in creating any prede- 25 air space. I have also illustrated the upper portermined pressure in the upper compartment B. tion 4 of the diffuser as insulated by surrounding The water to be cooled is either drawn in through pipe or nozzle 8 with an air jacket between it and opening in, by reason of the reduced pressure, or the portion 4. Of course, any suitable insulation is pumped in as conditions require; and this water 20 may be provided in either case. Intermediate spills over the annular weir 9, falls to the botthe height of the upper chamber B an annular tom of the upper compartment and is drained water spillway 9 is provided having inlet ill for through pipe H. As this water to be cooled enthe refrigerant or water to be cooled. Just above ters the upper compartment and falls over the the partition between the two chambers B and C weir, it is subjected to a sub-pressure materially 5 is an outlet H for the cooled or chilled water less than that corresponding to its entering temwhich collects .on the top of the partition. perature. The result is that a part of this en The lower chamber is provided with an upper tering water is immediately vaporized and these outlet l2, leading to a secondary vacuum device vapors are entrained by the steam jet leaving such as the motor-driven vacuum pump I3, shown nozzle 3 and compressed in difiuser 4 and dis- 4 in Figure 1 as mounted on the shell and driven charged into the lower compartment C. by electric motor 14. This, of course, may be The latent heat liberated by this vaporization replaced by any other type of vacuum-device, such of a part of the water to be cooled is withdrawn as a steam jet ejector. The lower chamber is fro-m the liquid as it falls over the weir 9. Conprovided with an internal annular water spillway sequently, the liquid passing out through open- I5, below which a series of staggered annular ing H is of a temperature corresponding to the 45 bafiies generally numbered I6 are arranged. sub-pressure created in upper chamber B. By a The lower head I! of the shell is provided with suitable design with proper proportioning and an outlet pipe ill for removal of the condensing supplying the proper quantities of steam and water and condensed steam. The pipes H and condensing Water, this unit may cool any desired 0 l8 may lead to centrifugal pumps l9 and 2B, or quantities of water through any desired temthese pumps may be omitted where gravity drainperature range and produce chilled water at any ing is possible. The spillway I5 is supplied with desired temperature above the freezing point. n n n W r ough inlet 2|. Other liquids than water may be admitted As will be noted, the inlet'lfl and the outlet ll through pipe ill and drawn out through pipe H of the evaporator chamber are located. behind the though water will be the liquid ordinarily used. 55

After the steam jet and entrained gas and vapors enter the diffuser, the velocity energy is reconverted into pressure energy and the mixture of propelling steam and entrained vapors is discharged from the lower end of the part 5 of the diifuser into the lower part of the chamber C Where it is condensed. As shown, this is a direct contact condenser, the water admitted through opening Zl falling over annular Weir I5 and striking the cascaded bafiles [6 so as to mix with and condense in counter-current flow the steam discharged from the lower end of the diffuser.

The non-condensible gases are drawn off through opening ii in the upper part of the lower chamber by any suitable device such as a motordriven vacuum pump or a steam jet or other suitable device.

While I have shown a direct contact type of condenser in the lower chamber portions of the shell or tank in Figures 1 and 2 of the drawings, I also contemplate using an indirect tubular or surface type condenser provided with tubes in the lower chamber through which condensing water may be circulated to condense the steam and vapors. Such a form is shown in Figure 3 wherein parts similar to those of the embodiment of my invention shown in Figures 1 and 2 are marked with the same numerals with the sufiix a added.

In this form, the condenser has tubes 22 connecting a pair of separate inlet and outlet chambers 23 and 24 at one side of the lower chamber C with a single compartment 25 at the other side of said chamber. In this form, the bafiles lfia take the form shown extending alternately from opposite sides and preferably overlapping each other. In this surface type condenser, the cooling Water is circulated from inlet compartment 23 through the tubes to compartment 25, and thence back to outlet compartment 24. The tubes, of course, extend on opposite sides of the diiluser 5a and through the shell of the compartment.

The advantages of my invention result from the cheapness, compactness and simplicity of the unit, all of which may be contained within one shell or tank. I thus materially reduce the cost by eliminating the conventional air or Vapor chamber containing the ejector suction, also by eliminating flanged connections in the difiuser of the compressor, and also by doing away with numerous piping connections. The conventional construction of such apparatus requires two separate tanks, one containing the evaporator and one containing the condenser. In my apparatus, the arrangement is simple, compact and eflicient. The insulation largely prevents the transmission of heat from the condensing compartment to the fluid being cooled and from the steam jet compressor to the fluid being cooled.

Within the scope of some of my claims, the two compartments may be in separate shells, but preferably in tandem relation, each chamber con taining a portion of the difiuser. Obviously, my construction gives a very compact and low cost apparatus. So far as I know, I am the first to enclose the difiuser in such apparatus partly within the flash chamber and partly within the condensing chamber.

The tank may extend in a horizontal direction instead of vertically, as shown, other means for insulation may be employed, the tank and its parts may be made up by welding, riveting or otherwise, as desired, and other changes may be made without departing from my invention.

Instead of a single nozzle 3, as shown, several nozzles may be used as conventionally employed in a steam jet compressor.

In large capacity units, two or more diffusers, such as 4 and 5, may be employed, each equipped with its own nozzle 3 or group of nozzles, in order to reduce the overall length of the apparatus. In such case, the apparatus may be the same as now shown, except that there are two or more diifusers arranged in the successive or tandem chambers shown.

Although not specifically illustrated in the accompanying drawings, the steam nozzle 3 may have its exterior surface insulated by any suitable means in order to prevent the transmission of heat from the steam nozzle to the evaporating compartment.

I claim:

1. In a liquid cooling apparatus of the steamjet-vacuum type, a housing enclosure, a partition dividing said enclosure into evaporator and condenser chamber portions, a diffuser extending through said partition and into said evaporator chamber and into said condenser chamber and being surrounded by said chambers, an ejector opening into and extending into said evaporator chamber and cooperating with the portion of said diffuser located within said evaporator chamber to feed a pressure fluid thereto and produce a vacuum in said evaporator chamber, an opening in the housing of said evaporator chamber providing an inlet for a liquid to be cooled, and means for condensing vapors fed to said condenser chamber by the portion of said diffuser located therein.

2. In a liquid cooling apparatus of the steamjet-vacuum type, a housing enclosure, a partition dividing said housing enclosure into a condenser chamber and an evaporator chamber having a tandem relationship with respect to each other, a diffuser extending through said partition through one end of said evaporator chamber and into said chamber, said diffuser also opening into and extending into said condenser chamber from the end thereof adjacent said evaporator chamber, an ejector opening into said evaporator chamber and cooperatively associating with the mouth of the difiuser portion extending therein, fluid inlet and outlet openings in the housing portion of said evaporator chamber, means feeding liquid to be cooled from the inlet opening substantially longitudinally with respect to the portion of said difiuser located within said evaporator chamber.

3. In a liquid cooling apparatus of the steamjet-vacuum type, a housing enclosure, a partition dividing said housing into an evaporator chamber and a condenser chamber, a diffuser extending through said partition into one end of said evaporator chamber and into an adjacent end of said condenser chamber, said difiuser having a converging-diverging outline from said evaporator chamber to said condenser chamber, the throat of said difiuser being located adjacent said partition and cooperating with said partition and the housing of said evaporator chamber to provide a receptacle for liquid to be cooled, inlet and outlet openings in said evaporator chamber for the liquid to be cooled, an ejector opening into said evaporator chamber and cooperating with the mouth of the portion of said diifuser casing located therein to supply a pressure fluid thereto, insulation about the portion of said diffuser located within said evaporator and between said p t g d aid CQndenser chamber, and means in said condenser chamber forcondensing fluid supplied thereto from the mouth of the portio of said diffuser located therein.

4. In a condenser having a suitable housing enclosure, a diffuser opening into and extending inwardly of said housing from one end thereof and being substantially surrounded thereby, a nest of cooling tubes in said housing arranged in a heat-transfer relationship with respect to wall portions of said diffuser, and condensing fluid inlet and outlet openings in said housing, said nest of cooling tubes being connected to said inlet and outlet openings.

5. In a condenser having a suitable housing enclosure, a diffuser opening into and extending inwardly of said housing from an end thereof and being substantially surrounded thereby, a nest of cooling tubes in said housing, said difiuser extending through said nest of tubes, condensing fluid inlet and outlet openingsin said housing, and partitions directing fluid flow through said tubes in a return path from said inlet to said outlet opening.

6. In a cooling apparatus of the steam-jetvacuum type, a housing enclosure, a partition dividing said housing enclosure into a condenser chamber and an evaporator chamber having a tandem relationship with respect to each other, a diffuser extending through said partition through one end of said evaporator chamber and into said chamber, said diffuser also opening into and extending into said condensing chamber from an end thereof adjacent said evaporator chamber, an ejector opening into said evaporator chamber and being arranged to cooperate with the mouth of the diffuser portion extending therein, fluid inlet and outlet openings in the housing portion of said evaporator chamber, said openings being located downstream of the mouth of the portion of said diffuser located in said evaporator chamber, means feeding liquid to be cooled from the inlet openings substantially longitudinally with respect to the portion of said diffuser located within said evaporator chamber, the flow of liquid from said means being directed in such a manner that it will be downstream of the mouth of the portion of said diffuser located within said evaporator chamber, and means opening into the housing of said condenser chamber and being arranged to supply means for con densing fluid entering said chamber through the mouth of the portion of said diffuser located therein.

'7. In an evaporator having a suitable housing enclosure, an ejector nozzle opening into and extending inwardly of said housing, a diffuser openinginto and extending inwardly of said housing substantially oppositely with respect to said ejector nozzle, said diffuser casing forming with said housing a receptacle for a liquid refrigerant, said ejector nozzle and said diffuser being surrounded by said housing and having a substantially cooperative relationship with respect to each other such that said ejector will directly discharge pressure fluid into said diffuser to produce a vacuum in said housing, inlet and outlet openings in said housing for a liquid refrigerant, and a spillway in said housing, said spillway being arranged to receive liquid refrigerant from said inlet opening and to direct a stream of liquid refrigerant substantially longitudinally of the walls of said diffuser.

LAWRENCE M. FORNCROOK. 

